A branch connector described above includes, as a basic structure, a pair of split housings capable of opening and closing in a manner clamping cables, and a relay contact to be electrically connected to a cable supported in a central supporting space of the pair of split housings in a closed state thereof.
The relay contacts are roughly classified into two known types. One of the types is provided with an insulation displacement groove configured to clamp an existing cable and a crimping terminal configured to crimp an additional cable (e.g., see patent literature PLT 1 set forth below). The other type is provided with a pair of insulation displacement grooves that are arranged in parallel with each other and configured to clamp the existing cable and the other cable, respectively (e.g., see patent literature PLT 2 set forth below).
The branch connector having the relay contact of either type is required to have a waterproofing structure for preventing the relay contact or the cables within the branch connector from contacting with water. As such, the applicant has been developing a technology for supporting a waterproofing gel within a gel-supporting space formed around the central supporting space (where the relay contact and the cables are supported) of the pair of split housings in the closed state.